Apparatus for cold reducing metal bars



June 16, 1953 G. L. FlsK APPARATUS FOR COLD REDUCING METAL BARS 10 Sheets-Sheet l Filed Oct. 25, 1945 June 16, 1953 G. l.. FlsK APPARATUS FOR COLD REDUCING METAL BARS l0 Sheets-Sheet 2 Filed Oct. 25, 1945 INVENTOR Gasa .F/'Sk BY m, m 1 M ATTORNEYS G. L. FISK APPARATUS FOR COLD REDUCING METAL BARS June 16, 1953 Filed oct. 25, 1945 June 16, 1953 G. L.. FlsK APPARATUS RoR COLD REDUCING METAL BARS Filed oct. 25, 1945 l0 Sheets-Sheet 4 l Il P/ TC l :lill 5" 59 Iig. 5.

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IEH LF INVENTOR P1 TCH qa June 16, 1953 G. L.. FlsK APPARATUS RoR com REDUCING METAL BARS 10 Sheets-Sheet 5 Gasa/L Fisk F i1ed Oct. 25, 1945 June 16, 1953 G. L'. FlsK 2,642,280

APPARATUS RoR coLD REDUCING METAL BARS- Filed Oct. 25, 1945 10 Sheets-Sheet 6 INVENTOR Gasa L. Fisk June 16, 1953 G. L. FlsK APPARATUS. FOR COLD REDUCING METL BARS 10 Sheets-Sheet '7 Filed oct. 25, i945 Gasa L. F/sk Jung 16, 1953 G. L.. FlsK 2,642,280

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G. L. FISK APPARATUS FOR COLD REDUCING vMETAL. BARS .June 16, 1953 16 sheets-sheet 1o Filed Oct. 25, 1945 INVENTOR Gas/a/FL. 475k 7 H .mm .PN m. WQN QN WJ Ng A m .n

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PatentedvJune 16, 1953 APPARATUS FOR COLD REDUCING METAL BARS Gustaf L. Fisk, New Fairfield, Conn.

Application October 25, 1945, Serial No. 624,344

l This invention relates to the cold-Working of metal bars of a great variety of sections, cornmonly known as merchant bars and shapes, whereby they may be finished to precise dimensions within close tolerances, and with improved physical properties.

In my co-pending application Serial No. 531,724, led April .1.9, 1944, for Method and Apparatus for Cold-Rollingy Metal Bars, which has been abandoned and superseded by my copending continuation application Serial No. 226,467, nled May 15, 1951, I disclosed and claimed the use of leaders and powerdriven tension rolls to pull the bars into the roll passes, and to maintain the bars under tension while reducing their sec-'- tion to desired size.` I also disclosed and claimed 'guiding means to keep round bars from turning on their own axes in the passes of a cold mill. Also disclosed and claimed in said application is the cold-drawing of bars, by aid of leadersand power-driven tension rolls to pull the bars into and through the dies.

Thepullof such tension rolls, however, is limited by the eiective pressure zone and by the maximum unit-loadsthat can be carried bythe materials of the belts and tires employed. To fully realize the advantages of the scheme involved, a much greater pulling capacity is desir'- able. For instance, the reduction of a les" 'diameter round of medium tensile strength to 1" diameter round vby Ycold-drawing through dies may require a pull of 15,000 lbs.; a figure beyond the practical capacity of a single pair of tension rolls.

So far as I am aware, no endless traction de- I vice has heretofore been available `for frictionally gripping a highly iinished steel merchant bar to exert a pull thereon close to its elastic lim-` it and without injury to its surface. [Such tension is highly desirablein that it permits heavy bar deformation without rapid hardening of the metal. Such devices as have been developed for ldesired tension are for'wire products', ystrip and sheet metal that can be bent'around a drum or coiled without injury. My invention, on the other hand, pertains to merchantbars which must be furnished in straight lengths .and can not be bent overa drum without injury to their structure.

To meet the needs of the trade as outlined above, I have invented a traction apparatus' which grips a bar over any reasonable predeter-A 15 Claims. (Cl. ZV1-2.1)

. 2 l. bar by friction up to its elastic limit. The necessary pressure is exerted through themedium of elastic cushions immediately supporting idler runways for traction chains, which in turnvsupport the belts and transmit the power from th driving sprockets to the belts. The pressure on the bar is controlled by adjusting the position.

of the idler runways and their supporting cushions, to cause the bar to compress the cushions on its passage through the apparatus. By these means I have provided a traction apparatus of adequate capacity. When only limited traction is required for sizing of bars, then the tension rolls of said copending application may be used or their traction augmented in the manner here-'- in disclosed.

Itis the object ofthe present invention to provide a novel traction apparatus of adequate pull'a ing capacity. It is a further object to eliminate the need for leaders, by using such a traction apparatus in conjunction with suitable guides to push the suc'- cessive bars into a roll vpass or die, as the case may be, and another traction apparatus on, the delivery side to exert pull onthe emergingbars.

Reciprocating machinery has been developed to grip the forward end of a bar and push it vthrough a die, so it can be 'grippedby thereciprocating jaws of av draw-bench. As compared to this practice the present invention provides for continuous cold-drawing, where each bar immediately follows its predecessor, by aid of one-way continuously operating bar entering and drawing machinery.

Another object of the present invention is to use a traction apparatus onthe entry side of a roll pass' or adiefto furnish back tens'ion onthe b ar during its-reduction, afterthis tractionk apparatus hasfservec'l to push the forward end of them from turning on their own axes.

Stillv anotherobject in Vcas'eof major reductions b ycold-rolling, is to provide for nprofitable vuse of 'such ends of the cold-rolled bars as may be over-size and out of shape due to rolling without benefit of tension.

Fora complete understanding of the inventionand the novel features thereof, reference is made'fto the'following detailed description and -the accompanying drawings. The latter lillustrate the power-driven traction apparatus and l diagrammatically the preferred practice of my movement of a roller runway, and a doublewedge adjusting rig;

Figure 4 is a detail plan view of the Elin-lis of the traction chain;

Figure 5 is a section on line V-V of Figure 4, showing the traction chain, and also a supporting roller;

Figure 6 is partly a side view `and partly a section of chain shown in Figure fi, also ,showing corresponding teeth ,of a sprocket wheel;

Figure 'I .is an enlarged view in elevation `and partly in vertical section, showing ,details lof `bea-rings and rubber sandwiches of roller runway;

kFigure 8 `is a side View of part of the equipment shown in Figure 7';

Figure `9 is a corresponding plan view of a .rubber sandwich;

Figure lo is a, cross section of the traction belts;

Figure 11 is a diagram showing the side elevation of `traction chains, sprockets, runway rollers,

idler rollers, belts .and pulleys Yof my traction apparatus;

Figures l2 and ,-13 show an .improved tire for the tension rolls specified in `said application, to increase their traction capacity.

Figure 14 is a cross section of the tire on line XIV-XIV of Figure 13, to show the tire in unloaded position, and Figures 14A and 14B show the construction -of the chain forming the tire tread;

Figure 15 is a diagram showing in elevation a preferred millarrangement permitting heavy cold reductions;

Figure 16 `is a diagrammatic plan `view of the traction chains and belts, guides and mill rolls shown in Figure 15;

Figure 17 is a similar plan View of a mill arrangement for moderate cold reductions, inc1ud- :ing cold-drawing to precise dimensions from end to end of bars;

Figure 18 is a similar plan view for sizing by .cold-drawing in idler rolls or roller dies, to preeise dimensions from end to end of bars;

Figure 19is a similar jplan view for coldvdrawing vor sizing in iixed dies, to precise dimensions from end to end of bars;

Figures 20 and 21 are enlarged side views and partly vertical sections and show respectively entry and delivery guide equipment in relation vto other parts of the traction Vapparatus of Figures 1 to 1l inclusive;

Figures 22 and 23 are a-plan view and a hori- -zontal section respectively, corresponding to Figures 20 and 21.

Figure 24 lis a section on line XXIV- XXIV of Figure 20; and

Figure 25 is an enlarged partial section on any of lines XXV-XXV in Figures 16, 17, 18, 119, 22 and 23.

Referring in detail 'to the drawings and for the present to Figures 1 through 3 and Figure Afeatures now to be explained.

In the .space between the driving sprockets g2, .2 on one hand and the idler sprockets 3, 3' on the other, and where the belts 4, d run in close proximity to one another, the chains I, I are backed up by runways 6 and 6' of a series of idler rollers 1 and 8, journaled in anti-friction bearings 3 and individually cushioned by rubber sandwiches I0 on movable girders II and Il. The motions vof these girders are simultaneous and towards or from the pass .line of the apparatus, to cause the belts 4, .4' to grip or release a ybar in transit 5.

The bottom girder Il, at both ends, is carried in bearings I2 on crank shaft I3, which is journaled in bearings I 4 of a carriage I5 with lugs I3, resting on wedges I'I and maintained central with respect to the pass line of the apparatus Lby contact with lugs I8 on the main housing I9. The top girder II' is similarly mounted by aid of corresponding items I2', I3', I4', I5', I3', Il", and |18', but the entire assembly of carriages I5', `crank shafts I3' and girder II' with runway E' is suspended by spring balance from the main housing I 3. 'This spring balance is accomplished by aid of Apins 2l! in girder I i', eye rods 2I, pivot blocks .22 journaled in the main housing I9 at 23, compression springs 24, washers 25 4and nuts 26.

The girders Il, .II have ways 2T! and2' in which cross heads 28 and 28 are fitted to slide. These cross heads are mounted on eccentrics 29 and 29' on shafts 30 and 30', journaled in stationary lbearings 3i and 32 and 3|' and 32. Miter gears 33 and 33 and shaft 34 connect the shafts 30, 30' for simultaneous and equivalent turning motions, effected by motor 35 driving shaft 3B through pinion 3B and gear 3l.

It will be apparent that the operation of motor 35 will turn eccentrics 29, 29 and cause cross heads 28, .28 to .force a movement of girders I I, II in longitudinal direction. But this movement will cause the crank shafts I3, I3' to turn in bearings I4, Idand move the girders II, II' with runways 6, 6", and thus the chains I, I' supported thereon, towards or from the pass line, so as to make the belts 4, 4 grip or release a bar 5 at the will of the motor operator. Provisions to allow for these chain and belt vmovements will be referred to hereinafter. The spring balance already described is designed to allow for required movements of the top girder and to balance approximately twice the weight of the parts suspended, to firmly hold this girder in place4 The bar-gripping drive just described is controlled by limit switch to provide -a fixed gripping motion, determined by eccentrics 29, 29 and crank shafts I3, I3. To allow for different sizes of bars and to vary the pressure applied to the bars, adjusting rigs are provided to vary the position of the gripping machinery, as will now be explained. To this end, the wedges II are furnished with and hold nuts 38 and 39 travel on a screw at the same rate but in opposite directions, and thus move the wedges towards or from one another. Each of the two screws 40 (Figures 1 and 3) is anchored'in longitudinal direction in a bearing 4I of the main. housing I0, so that the wedges I'I in their movements remain centered with respect to the pass line of the traction apparatus.v Each of the two screws 40 is connected by means of gearing 42 and 43 to a shaft 44 (Figures 1, 2 and 3), and this shaft has a worm-wheel 45 engaging a worm 46 for operation by hand-wheel 47.

This manually operated adjusting rig pro-'vides for the movement of runway 8 towards or from the pass line, as required, while `maintaining the runway parallel with the pass line. A similar rig actuating wedges Il' and including corresponding items 38A', 39', 40', 4l', 42', 43', 44', 45', 46 and 4l', `serves for hand `adjustment of runway 0' with respect to the pass line. Items 38', 30 and 4i' are not visible'in the drawings but theirlocatio-n and construction are evident from those of corresponding items 38, 39 and 4I. These adjustingrigs thus provide for accurate setting of pass opening, to obtain desired grip- V These nuts vhave l right and left hand threads respectively and' individua sandwiches by aid of nuts` 69 and spring washers 10.

The individual cushioning of the bearing 9 prevents overloading of any of the rollers l and 8 or their bearings. To illustrate, assume that the manually operated Aadjusting rigs, already described, have been set for a given size of bar,

to cause a deflection of the rubber sandwiches I0 corresponding to a total load of 50,000 lbs. on

' (Figures 1 and l1), the load carried per roller gures 2,500 lbs., or 1,250 lbs. per bearing 9. The

`roller vcounted not effective is the one next to the driving sprocket, which has to sustain the load incidental to the angularity of the chain pull by the sprocket with respect to the direction of chain travel on the runway. As the rear end of the bar passes through the traction rapping force on a bar `li when Vthe gripping drive is operated.

The chains I, I', in their travel from driving sprockets 2, 2 to` idler sprockets 3, 3', are supported on idler rollers l0 and 43', which are journaled in anti-friction bearings 49 and 49 and cushioned by rubber sandwiches 50 `and 50' for support on the` main housing I9.

The detailed construction oi' chains I, I' is illustrated by Figures 4' through 6, The chain blocks 5i and 52, which form `the links of the chain when assembled on pins 53, fit one another with smailclearances 54 to provide a nearly continuous support for belts 4, 4' in longitudinal direction, while thesebelts are solidly supported on the individual chain'blocks and contained within their guiding ribs 55 and 5B. pins 53 are fastened toi chain blocks 5I by rivetsv 57, while'` chain blocks 52 are free to pivo-t on these pins. The pitch 58 of the chain is selected to provide apertures 59 between the chain blocks 52 to Yfit the teeth B0 of the sprockets. On the inside of the endless chains, each chain block hasA a projecting ridge 6I which fits corresponding grooves E2 in the idler rollers 1, 8, 40 and 48' and serves to steer th-e Chains centrallyvof the pass line on runways 6, 6'. I

The bearings 9 for rollers 'l and 8 of runways 6, 6', are individually cushioned in arnanner now to be explained'with particular re-ference" to Figures 7 through 9. A closespacing of these rollers is desirable to lend continuous support to the individual blocks 5lv and 52 of chains I, l", as the-y pass over the runways and E'. To this end, the bearings 0 on either side of each runway have been staggered, to place the bearings for roilers 'l in one row and thoseof rollers 0 in another row; accomplished by lengthening' the shafts of rollers] to suit. vlilach bearing is supported on what is commonly known las a rubber sandwich I0, which'injthis case consists of a cushion 53 of rubber or .rubber-likernaterial, plates 64 and 55 and bolts 65, all bonded together by suitable vulcanizing and readily obtainable from manufacturers of rubber goods. The several sandwiches are fastened to girders ,I I, I I' by means of tap bolts 61 and spring washers 68, and the bearings 9 are secured to the The 'figures 25 square inches.

paratus, the loads on the lindividualrollers are' removed one by one, while the remaining rollers, still deflected by the bar, carry their normal loads only, controlled by the settingof the adjusting rigs.

The chain drives, rollers, bearings and rubber sandwiches involved in a. machine of the. capacity above referred to can readily be furnished by manufacturers, and traction requirements rather than limitations of machine elements will dene the apparatus and capacity best suited to any particular purpose.

Belts 4, 4', shown in cross 'section-in Figure l0, are preferably made of neoprene or other oilresisting rubber or rubber-like material. Part of the belt thickness is made up of layers of duckll and so called friction rubber l2, and the balance of alayer of rubber '13.grooved at M to form a pass for a bar 5. Although the groove 't4 is made to fit a particular size of bar, the same set of belts may be used for several sizes.V As an example, it is my intention to use one set ci belts for rounds 'from l" to l" in diameter. If the width of effective belt contact on a 3A" diameter bar be taken at` 1/2", then the contact area per belt for a vtraction apparatus of the capacity above referred to, with a runway length of 50", This gives an average unit pressure of 2,000 lbs. per square inch, which appears entirely feasible and practical for the belting material I have proposed.. Taking the friction coeiiicient of neoprene on a smooth steel bar at .20, the total traction capacity of the two belts of the apparatus figures 20,000 lbs.

The novel tire, shown in Figures 12 through 14B, has the purpose to increase the traction capacity of the tension rolls of my co-pending application Iabove referred to. Except for the tires, the roll centers, and the cross section and material of the belts, there is no change in construction of these tension rolls. 1

Cushions 'I5 of rubber or rubber-like material and their supports 16, preferably o-f steel, are bonded together to form segments TI. Such segments are tted to the roll center 18 to form two complete circles and are secured in this position by bolts "I9, to form a exible tire element. The tire tread is formed by an endless chain of'co'nstruction shown in Figures 14Al and 14B, and traction on a bar' is exerted by aid of belts 8i ofrubber or :rubber-like material and of same cross sectionas that shown in Figure 10, Retain- Assume that ing rings :82 aire fas-tened to the roll center 78 by bolts 815 and serve to limit the Lside-wise expension of cushions i under load. rhis` expansion can be further limited by insertion ol shims 84 indicated in dotted lines.

It is a Well Vknown fact that rubber .is practically non-compressible and that its deflection and load carrying capacity in one direction are contingent on space for expansion in other directions. It is my purpose to take a'dvanage of these characteristics by allowing the rubber cushion to deflect freely until a pressure zone B5 of suitable length has 'been established, and then Ato limit further expansion in one direction so as to increase the load carrying capacity of the tire beyond that corresponding tofree expansion.

The application `of my traction apparatus and and/or traction rolls to the Aart lof cold-reducing metal bars is aided by guides, indicated in Figures 15 through 19 and more fully illustrated in Figures 2G through 25. Y

For a clear understanding of the functions of the guides shown in Figures 2) through 24, I now Iexplain the preferred operation of a traction apparatus, 'indicated generally at t5 in Figure l5, in gripping a bar to exert traction thereon. With the bar gripping mechanism in oli posit-ion, the adjusting rigs are set for desired gripping force on the size of bar to be handled. The .spocket drive is then started to set the chains ii, in motion and cause the belts d, 4 to travel at Idesired bar delivery speed. The -bar may now be fed to the apparatus by hand or mechanically, but in either event entry guides lli will serve to direct its forward end to the pass line, by virtue of bell-mouth 88, guiding surfaces 89 and idlers S0. In feeding the bar further into the apparatus, its forward end vpasses beyond the entry guides but is restrained from moving up or down by the belts d, Ii', which travel in close proximity to the bar but so far exert no pressure on it. Delivery guides 9| have guiding surfaces s2, which allow for a limited deflection of the end of the bar up or down. Should the belt clearance be sufciently large, however, to permit the bar to leave the grooves 'I4 in the belts, then its forward end may deect in sidewise direction to strike guiding surfaces 931 of bellmouth 94, to again be directed to the pass line. When the forward end of the bar reaches idlers 95 and is thus held accurately to the pass line by delivery guides 9| as well as entry guides 81the bar gripping drive is operated and the predetermined traction applied to the bar, now caused to travel at the predetermined .delivery speed.

The idlers 90 and 95 are journaled in antifriction bearings S6 and facilitate bar passage with a minimum of guide clearance. The guides 8'! and 9| are held in guide boxes 9-'1 by bolts 58 with nuts S53, and their position is adjustable rby aid of shims l. The guide boxes are supported on rest bars and |532 and are clamped in position on ways |03 by blocksy |04, bolts |05 and nuts iBS. Spring I serves to retain block |013 and bolt |05 in position' controlled bythe setting of nut |96, when releasing or clamping the guide boxes. The rest bars are secured to the main housing I9 of the traction apparatus on pads |98 and H39, by bolts HB and nuts These pads are shown in Figures l and 2 as well as Figures Zit-through 24.

Referring now to Figures l5. 16 and 25, the traction apparatus 36 has the function to force a bar 5, indicated in Figure 25, into passes in driven mill rolls I|2 and H3, which passes are predicated on reductions vin section Varea of lsuch magnitudes as to preclude bar .entry by tractve force of the rolls themselves. To prevent the bar 5 from buckling under the tractive force exerted by ,apparatus 86, guides H4 and ||5 with idlers |16 are provided, which together with identical idlers of delivery guides 9| serve to render lateral support to the bar at regular intervals between the runways 6, 6 of the traction apparatus (see Figure 11) and the mill rolls ||2. The guides H4 are preferably fastened to a separate stand in front of mill rolls ||2, while the guides 5 are held by customary guide boxes and rest bars, the latter attached `to the housing for the rolls H2. Figure 25 further illustrates the manner 'of guiding and laterally supporting the bar in guides 9|, H4 and ||5.

With further reference to Figures 15 and 16, delivery guides ||1 and entry guides ||8 are preferably .of the type Aillustrated in my copending application No. 531,724, Figures 18 through 22. `In conjunction with guides I9, .also of the cross 'section shown in Figure 18 vof said application, they cover the space between mill rolls I2 and fl I3 and vserve to keep the bar 5, now reduced to an oval section, from buckling under the longitudinal loading exerted by traction apparatus V86 in forcing lbar entry into rolls |3. The delivery guides |20 of rolls ||3 merely serve to direct the emerging lbar with suicient accuracy to bring its forward end within the bellmouth of entry guides l2! of the next traction apparatus, indicated generally at |22. From there on and through mill rolls |23 and |24 and through traction apparatus |25, the bar guiding equipment is merely repeated with such modiiications as called for by the changing size and shape of the bar. 1

Whereas the guides ||8 and ||9 serve to keep an oval section from buckling, they also serve to keep an oval bar from twisting on its own axis in the space `between rolls |2 and ||3, as required when `employing my method for the reduction of hot rolled commercial rounds into cold rolled rounds 4of much smaller size and great accuracy. The latter function of guides |1 and 8, referred to in said co-pending application, is predicated on pass reductions of such magnitude that the oval produced from the commercial round can be made suiiciently pronounced, to permit of definite guiding and prevention of twist. In case of smaller reductions, the tendency to such twisting is correspondingly decreased and less detrimental to the accuracy of product. Furthermore, the cold and stiff bar as a whole is held against turning on its own axis by the powerful gripping action of the traction apparatuses; a further insurance for accuracy of product.

It should be noted in this connection that the push exerted by traction of apparatus 86 continues until the forward end of the bar 5 is gripped in traction apparatus |22. From then on the apparatus 86 ceases to push and serves instead to exert pull or back tension on the bar; all by speed control of traction apparatuses and mill rolls, now to be explained.

By nominally operting the traction belts of apparatus 8S at a speed somewhat below the entry speed of mill rolls ||2 and those of apparatus |22 ata speed somewhat in excess of the corresponding continuous delivery speed of mill rolls ||3, the bar 5 is held under tension between traction apparatuses while the driven mill rolls ||2 and ||3 reduce its section area. Bv

9. duly controlling also the speeds of mill rolls |23 and I 24 and of the traction belts of apparatus |25 with respect to traction apparatus |22, tension is also maintained on the bar in passage from apparatus |22 to apparatus |25 while driven mill rolls |23 and |24 further reduce its section. y

' It will be noted that the front end of each bar is reduced in mill rolls ||2 and ||3 without V benet of tension until the bar has advanced far yenough to be gripped in traction apparatus |22. Also the rear end of each bar is reduced inrthese rolls without benefit of back tension, after it leaves the traction apparatus 86 and the mill rolls ||2 respectively. *This lack of tension and back pull will result in bars slightly over size at the ends. The performance is repeated in mill rolls |23 and |24, although the discrepancies are bound to be reduced rather than increased in these rolls due to smaller pass reductions. If bar requirements are merely for exact size within precision tolerances, I propose to cutthe coldrolled bar into required lengths and then to coldreduce the over-sized end lengthsto exact dimensions in eithery of the layouts shown in Figures 18 and 19 respectively and in a manner to be explained. I f exacting quality requirements preclude such use of` the. end lengths, however, I propose to subject them to annealing for cold-reducing into bars of smaller size.

The layout shown in Figure 1'7 is predicated 16, the functions and construction of which have already been explained. -Since the final size of the product is determined by the hole in the die, however, the tendency to twisting or. turning of the bar, as above referred to, is new of minor importance and the product is of uniform'section from end to end of bars.

' Figure 18 shows my improved traction rolls r |32 and |33 used respectively to push the forward ends of bars throughthe reduction passes of idler rolls |34 and |35v and to pull the bars through these passes, principally for the purpose of sizing of hot-rolled products. During` the pulling operation, back tension on the barbetween the traction rolls |32 and the idler Arolls |34 can be maintained at any suitable ligure, by speed control of the traction rolls |32.-. Sincethe pass reductions required are small and any `tendency ofthe bar to turn in the roll passes is checkedby thegrip of the traction belts |35 and |31, the product -is ofA accuratesize from ,end to end of bars.- In case the layout be used for ex-v treme tolerance requirements, however, it may be necessary to divide the drawn product into suitablelengths and then to subject over-size Vend lengths to further treatment.

The layout shown in Figure 19 is predicated on sizing or cold-drawing in a single reduction. Traction apparatus |38 serves to force the forward ends of the bars through the die |39 to a point where these ends canbe gripped by traction apparatus |40 for pulling thebars through the die. It also serves to furnish back pull on the bars during the drawing operation, when suitable bar tension is established by speed control ofthe traction belts `of apparatuses |38 and |49. "The product is identical in size from end to end of bars. To attain larger reductions it is merely necessary to add required dies and traction means to the pass line.

The entry guides |4| of the traction rolls |32 and |33 are of the type described in connection with the tension rolls of my co-pending application above referred to, and the construction and purpose of other guides indicated. in Figures 18 and 19 will be apparent by comparison with guides shown in Figures 15 and 16.

With respect to over-size end lengths above u referred to, Aitrwill .be understood that such duce its over-sized end portion to correct size,

Vwhile the tractionrolls |32 are caused to idle along.; In case of layout shown in Figure. 19, the

vtraction, apparatus ljt'would push the good end of the bar through the die |39 with little or no resistance, andV traction apparatus" |119 would pull the over-sized end portion through the die to correct size.`

With further reference to traction apparatus and'tractionrrolls (Figures l1, 15 and 18), pulleys |42 and |113 respectively provide for adjustment of belt tension to compensate for stretch or wear of traction belts d' and |36 and 31. Any conventional adjusting rigs may be used, and such a rig suited to pulleys |653v of the traction rolls is illustrated in my co-pending application above referred to. Idler sprockets 3, 3 should also be adjustable, in customary manner, to allow for desirable take-up of trac- Driving sprockets 2, 2 and idler sprockets 3, 3' should preferably be rubber `mounted on respective shafts in any generally approved manner; the former to soften the shocks when the traction loads are applied to the bars by operation ofthe gripping-drive, the latter to better accommodate the chain movements when the gripping drive is operated. These chain movements are otherwise compensated for by the end rollers: of runways 6, 6 and the idler rollers 48, 43', which are mounted in antifriction Ybearings and vcushioned on rubber sand-l Wiches as already explained. 5

Itwillbe noted that the mill arrangements and` layouts shown in Figures 16 through `19 permit of continuous operation, one barfollowing another Without stoppage of-mill rolls or traction belts','as close together as they can be fed tothe traction apparatus or-traction rolls.

Straight lengths o f precision rounds may be produced -from hot-rolled commercial rounds in cooling bed lengths .or in coils. Inthe former case, suitable plant layouts are described and'illustrated in my Patent 2,369,730 for Method of Rolling Metal Bars. By substituting appropri- 'ate mill arrangements or layoutslof my present Figuresis through' 19 for mins '1, l2, s1 and 92 of Figures 11 and 12 of said patent, A of cooling bed lengths to the reductionmills and the `.dspositionnof ,thecold-reduced product is the handling asians() readily understood. When coldero'lling or drawing from hot-rolled and coiled commercial rounds, the. coil transfer, uncoiler and coil carrier described in my copending application above referred to, would serve to handle and open thev coils and to. feed the ends of the bars to any of the layouts of present. Figures 16. through 19.. Theproduct is preferably handled in the manner `rcalled for in the same application with reference 4toits Figure 17.

n Subject matter disclosed but not claimed in this application is claimed in my divisional applications Serial No, 9,508, filed February 19, 1948, and Serial No. 244,641, filed August 31, 1951.

Whereas my novel method of ooldfreducing has been described with particular referenceA to rounds, one of the. more diilicult sections to roll to precise dimensions, it will be understood that my method lends itself equally Well to precision cold-.rolling or drawing of other sections.

It will be apparent that thetractive force of my novel apparatus is equally well suited for pushing a bar into a roll pass or through a hole in a die, if the stiiness of the bar against buckling be` augmented by lateral supports to force the bar, into desired engagementA and direction of travel, the pass reduction notwithstanding. in this manner I avoid the need for leaders, called for in said corpendi-ng application.

I` also. provide a novel method for continuous 3.

cold-.drawing ofV metal bars, not to my knowledge hitherto. accomplished By using my traction apparatus on the entry as well, as the delivery side of a roll passor a die,

desirable back tension can be maintained on the entering bar by speed control of the traction belts, to. further lessen the work of bar deformation in the pass or die and prevent more. rapid hardening of the. metal.

In rolling from commercial rounds, the use of a traction apparatus on the entry side ot the mill permitsA the bar to be held in the grip ofthe traction belts as it enters the mill, to keep it from turning in the rol-l passes. This is conducive (and: incase. ci large reductions, essential) to. accuracy or product.

E have also disclosed a novelV method for recovery of over-sized end portions oitbars reduced by.V my colderoiling. method, so that the scrap loss in cold reduction by any ofthe. proceedings I have disclosed. would be. practically nil.

Although l" have described certainv preferred forms and practices or my invention, itsadvantages may be realized in other ways Within the scope of the. appended claims.

relai-m:

l. Traction apparatus foradvancing elongated articles in the. direction of the lengththereof comprisingv two generally coplanar endless trac-A tion elements. having respectively opposed sub.- Stautallr parallel. residues.,- meansv for driving the gements se that at, Said reaches thereof they move the, direction. at the, same speed.. mounting Structures; respectrelv.V disposed at least. in part, generally' within the endless trat.- tion nements. pressing devices, also respectively disposed at least4 in part generally within the endless.V traction elements` behind saidk reaches thereof respectively carried., by the` mounting structures and` adapted to press said reaches toward each other, positioning means predeter-- mining the relative positions of the pressing devices andn a connection between at least one of the mounting structures and' the corresponding pressing device rapidlyv vshiftable to dispose the 12 pressing devices in relativeY positions predeter4 mined by the positioning means.

2. Traction apparatus for advancing elongated articles in the direction of the length thereof comprising tivo. generally coplanar endless traction elements havingrespectively opposed.' substantially parallel reaches, means for driving the ele'mentsso that at said reaches. thereof they move. in the same direction at the same` speed, mounting structures respectively disposed at least in part generally within the endless traction elements, pressing devices also respectively disposed at least in part generally Within the endless traction elements behind said reaches thereof respectively carried by the mounting structures and adapted to` press said reaches toward each other, connecting means between at least one ci the mounting structures and the correspond'- ing. pressing device movableto dispose the press ing devices in selected accurately predetermined relative positions and a single operating element mechanically connected with the connecting means for operating the same toso move the pressing device.

3. Traction apparatus for advancing elongated articles in the direction of the length thereof comprising two generally coplanar endless traction elements havingrespectivelyy opposedv substantially parallel reaches, means for driving the elements so that at said reaches thereof they move in the same direction atthe same speed, mounting structures respectively disposed at least in part generally wit-hin the endless traction elements, pressing devices also respectively disposed at leastV in part generally within the endless tractionl elements behind said reaches thereof respectively carried by the mounting structures and adapted to press said reaches towardeach other, connections between at least one of the mounting structures and the corresponding pressi-ng device movable to dispose the pressing` device in selected accurately predetermined relative positions and a single operating element-mechanically connected with the connections to positively simultaneously operate theconnections.,

4. Traction apparatus for advancing elongated articles in the direction of, the length thereof comprising two generally copla-nar endless traction elements havingrespectively opposedl sub.- stantially parallel reaches,v means for driving the elements so that at said reaches thereof4 they movein the same direction at the same speed, mounting structures respectively disposed at least in part generally Within the endless traction elements, pressing devices also respectively disposed at least in part generally within the endless traction elements behind said reaches thereof respectively' carried by the mounting structures and adapted to press said reaches t9- ward each other, connecting means, between one of the mounting structuresV and the lcorresponding pressing device, separate connecting means between the otherr of the mounting structures and thecorresponding pressing device and means for simultaneously operating the lrst mentioned and second mentioned connecting means to simultaneously movethepressingdevices toward or away fromeach other.

5. Traction apparatus for advancing elongated articles in the direction of the length thereof comprising two generally coplanar endless traction elements havingi respectively opposed substantially parallel reaches, means for driving the elements so that at said reaches thereof they rapidly shiftable to alter the distance between the pressing devices.

6. Traction apparatus for advancing` 'elongated articles in the direction of the length thereof comprising two generally coplanar endless traction elements having respectively opposed substantially parallel reaches, means for driving the elements so that at ysaid reachesv thereof they move in the same direction at the same speed,

mounting structures respectively disposed at least in part generally within the endless traction elements, pressing devices also respectively dis"- posed at least in part generally within the endless traction elements behind said reaches thereof respectively carried by the mounting structures andr adapted to press said reaches toward each other, crank means connecting at least one of the mounting structures and the corresponding pressing device and means operating the crank means to alter the distance between the pressing devices.

'7. Traction apparatus for advancing elongated articles in the direction of the length thereof comprising two generally coplanar endless traction elements having respectively opposed substantially parallel reaches, means for ydriving the 'i14 comprising two generally coplanar endless traction elements having respectively opposed substantially parallel reaches, means for driving the elements so that at said reaches thereof they movel in the same direction at `the same speed,- mounting structures respectively disposed at least in part generally within thev endless traction elements, pressing devices also respectively disposed at least in part generally within the endless traction elementsbehind said reaches thereof respectively carried by-the mounting structures and adapted to press said reaches toward each other,

a plurality of cranks connecting each of the mounting structures and the corresponding pressing deviceand means simultaneously moving both `pressing devices, each relatively V.to the corref spending-mounting structure, to-cause turning elements so that at said reaches thereof they move in the same direction at the same speed, mounting structures respectively disposed at least in part generally within the endless traction elements, pressing devices also respectively disposed at least in part generally within the endless traction elements behind said reaches thereof respectively carried by the mounting structures and adapted to press said reaches toward each other, a pair of similar generally parallel cranks connecting at least one of the mounting structures and the corresponding pressing device and means for simultaneously operating the cranks to alter the distance between the pressing devices.

8. Traction apparatus for advancing elongated articlesin the direction of the length thereof comprising two generally coplanar endless tractionV elements having respectively opposed substantially parallel reaches, means for driving the elements so that at said reaches thereof they move in the same direction at the same speed, mounting structures respectively disposed at least in part generally within the endless traction elements, pressing devices also respectively disposed at least in part generally within the endless traction elements behind said reaches thereof respectively carried by the mounting structures and adapted to press said reaches toward each other,

a plurality of cranks connecting at least one of the mounting structures and the corresponding pressing device and means moving the pressing device relatively to the, mounting structure to cause turning of the cranks and consequent alteration of the distance between the pressing dev1ces.

9. Traction apparatus for advancing elongated articles in the direction of the length thereof mounting structures toward and of the cranks and consequent simultaneous movement of the pressing devices toward or away from eachother..`

. l.10. Traction apparatus for advancing elongated articles in the direction of the length thereof comprising twogenerally coplanar endless traction elements having respectively opposed substantially parallel reaches, means for'driving the elements .so that at said reaches thereof they move in the same direction at the same speed, mounting structuresrespectively disposed at least in part generally within the endless traction elements,pressing devicesl also respectively disposed at least in part generally within the endless 'traction elements behind said reaches thereof respectively carried bythe mounting structures and adapted to press said reaches toward each other, a connection .between at least one of the mounting structures and the ycorresponding pressing device rapidly; shiftable to dispose the pressing devices in selected accurately vpredetermined relative positions and means for adjustably positioning at least one of the mountingv structures toward and away from said reaches of the endless traction elements. 1l. Traction apparatus for advancing elongated articles in the direction of the length thereof comprising two. generally coplanar endless traction elements having respectively opposed substantially parallel reaches, means for driving theeleme'nts so that at said reaches thereof they move in the same direction at the same speed, mounting structures respectively disposed at least inv` part generally within the endless traction elements, pressing devices also respectively disposed at least in part generallywithin the endless traction elements behind said reaches thereof respectively carried by the mounting structures and adapted to press said reaches toward each other,., connecting means between one of the mounting` structures and the corresponding pressing device,l separate connecting means betweenV the other of.' the mounting structures and the corresponding pressing device, means for simultaneously operating the rst mentioned and second mentioned connecting ymeans to simultaneously move the pressing devices toward or away from each other and means for adjustably positioning each of the Y away from said reaches of the endless traction elements.

12. Traction apparatus for advancing elongated articles in the direction of the length thereof 'comprising two generally coplanar endless traction elements having relatively opposed substantially parallel reaches, means for driving'- the elements so that at said reaches thereof they move in the same directlon at the same speed, mounting structures respectively disposed at least aeriaeeo in part generally within the endless traction elements, pressing devices also respectively disposed at least in part generally Within the endless traction elements behind said reaches thereof respectively carried by the mounting structures and adapted to press said reaches toward each other and separate means for adjustably positioning each ci the mounting structures toward and away from said reaches of the endless traction elements.

13. Traction `apparatus for advancing elongated articles inthe direction oi the length thereof comprising two generally coplanar endless traction elements having relatively opposed substantially parallel reaches, means for drivingl the elements so that at said reaches thereof they move in the same direction at the Isame speed, supporting means, mounting structures respectively disposed at least in part generally within the endless traction elements and supported by the supporting means, pressing devices also respectively disposed at least in part generally within the endless traction elements behind said `reaches thereof respectively carried -by the mounting structures and adapted to press said reaches toward each other and means including e, slidable wedge block wedgingly engaged between the supporting means and at least one of the mounting structures for adjustably positioning the mounting structure relatively to the supporting means.

14. Traction apparatus for advancing elongated articles in the direction of the length thereof comprising :two generally .coplanar endless traction elements having relatively opposed substantially parallel reaches, means for driving' the elements so that at .said reaches thereof they move in the same direction at the same speed, supporting means, mounting structures respectively disposed at least in .part generally Within the endless traction elements and `supported by the supporting means, pressing devices also respectively disposed at Aleast in part genorally Within tthe endless "traction elements behind said reaches thereof respectively carried by the mounting structures and :adapted to press said reaches toward `each other, a plurality of adjustable connections between the supporting means and at least one of the mounting structures and means -for simultaneously operating r16 said connections for adjustably positioning the mounting structure relatively to the supporting means.

15. Traction apparatus for advancing elongated articles in the direction of the length thereof comprising two generally coplanar endlesstraction elements having relatively opposed substantially parallel reaches, means for driving the elements so that at said reaches thereof 4they move in the same direction lat the same speed, supporting means, mounting structures respectively disposed at least in part generally Within the endless traction elements and supported by the supporting means, pressing devices also respectively disposed at least in part generally within the Aendless traction elements behind said reaches thereof respectively carried by the mounting structures and adapted to press `said reaches Vtoward each other, a plurality of adjustable connections between the supporting means and at least one of the mounting structures, eachof said connections-including Wedge means and screw means yfor operating the vif-edge means, and means for simultaneously operating the screvvnmeans to adiustably position the mounting structure relatively to the supporting means.

GUSTAF L. FISK.

` References Cited in the file of this patentv UNITED STATES PATENTS Number Name Date 548,637 Greenfield Oct. 29, 1895 1,113,474 Norton Oct. 13, 1914 1,184,972 Lloyd May 30, 1916 1,321,463 Lloyd Nov. 11, 1919 1,568,594 Flint Jan. 5, 1926 1,776,775 Biggert Sept. 30, 1930 1,779,479 Leech, Oct. 28, 1939 '1,991,514 Herman et al Mar. 14, 1933 1,994,885 Seeley Apr. 18, 1933 2,060,782 Armstrong Nov. 17, 1936 2,065,855 `Ferm Dec. 29, 1936 2,971,999 Dike Feb. .23, 1937 2,194,212 Sendzimir' Mar. 19, 194!) 2,236,751 'Dine Apr. 1, A1941 2,297,295 Flintjer Sept. 29, 1942 .2,369,730 Fisk Feb. 20, 1945 2,397,446 -Herz Oct.- 23, 1945 `.21,400,690 Fisk May 21, 1946 

